Ans: 1) Green House: Whenever, sunrays heat the surface of the earth. The heat generated is radiated from the earth. There are some gases whose presence in the atmosphere traps the radiated heat causing the heat of the earth surface. This phenomenon is known as green house effect.
2) Whenever the amount of green house gases( eg. carbon dioxide, methane, water vapour, etc) increases in the atmosphere, the radiated heat gets trapped causing the increase in surface temperature of the earth.This phenomenon is known as global warming.
